The present invention pertains generally to air purification, and more particularly to a method and apparatus in which an attachment to a fan blade is utilized to remove pollutants from the air.
Fans are commonly used to increase comfort by moving air and improving ventilation. Fans have been used in residential, institutional, and commercial facilities for many years and are manufactured by a number of companies worldwide. There exist a number of patents teaching the use of filters, or filter fasteners, blade covers or specifically designed blades to modify fans and/or their blades for capturing pollutants or foreign matter. For example, U.S. Pat. No. 6,174,340 shows a room air filter apparatus including a multi-sided housing having longitudinally spaced first and second ends, a plurality of sides between the first and second ends, and a plenum inside the housing. Each of the sides has an empty space frame by outer edges of the housing side. A fan is mounted to the housing and is operably disposed, preferably, within the plenum to draw air from the plenum and to exhaust the air outside of the housing. Filter panels are removably attached to the outer surfaces of the edges and filter material is mounted in the panels to cover the empty spaces. Magnets mounted on edges of the panels may be used as attachment devices as well as other devices for clipping the panels onto the outer surfaces of the edges of the housing. The filter material is preferably a self-charging electrostatic washable material.
U.S. Pat. No. 5,912,369 illustrates self-adhesive fibrous air filters that are universally compatible with devices that require filtered air and devices that provide filtered air. The self-adhesive air filters are fabricated from a flexible fibrous air filter blank composed of, for example, polyester batting, that is coated with an air permeable non-drying adhesive that has been vacuumed into the interstices of the fibers. A template serves as a protective cover for the non-drying adhesive and enables a user to shape and/or size the blank to configurations that are compatible with the air intake regions of the devices on which the self-adhesive air filters are to be installed.
U.S. Pat. No. 5,795,131 discloses a ceiling fan for cleaning air in a room wherein each blade of the ceiling fan has a cavity open to the top and bottom surfaces of each fan blade and a filter unit in each of the cavities but within the confines of the fan blade such that, when the ceiling fan is operated, the airflow created by the ceiling fan will be forced through the filter unit from the bottom surface through to the top surface, wherein the filter units can collect airborne particles.
U.S. Pat. No. 5,591,006 comprises a removable, washable decorative cover for each thin, flat fan blade of a paddle-type ceiling fan. The decorative cover includes a main sleeve of uninterrupted tubular shape, each end of which is open, and formed of highly elastic and expandable decorative fabric, preferably SPANDEX. The main sleeve is of sufficient elastic strength and sized substantially smaller in width than the width of the fan blade whereby, when mounted over a preselected main portion in length of the fan blade, the gripping action of the elastically stretched fabric conformingly against the surface of the main portion of the fan blade is sufficient to prevent movement therebetween when the ceiling fan is in operation. The cover may also include an end sleeve formed of the same elastic fabric and transverse width, one end of which is open, the other end of which is closed. The end sleeve conformingly fits over the distal end of the fan blade in either spaced, abutting or overlapping orientation on the distal portion of the fan blade with respect to one open end of the main sleeve. The end sleeve is likewise of sufficient elastic strength, when stretched to cover the distal portion of the fan blade, to remain stationary on the distal end of the fan blade during ceiling fan operation
U.S. Pat. No. 5,562,412 consists of a fan apparatus with a filter affixed to one or more of its fan blades such that the rotating fan blades carry the filter or filters through a medium to extract pollutants.
U.S. Pat. No. 5,370,721 describes a ceiling fan filter for filtering the air in a room having a ceiling fan. The ceiling fan filter is made from at least one layer of resilient polymeric fiber filter material. Each layer has a length, a width, an upper surface, a lower surface and two side edges which extend along the length of the layer. A narrow compressed strip is formed in the filter material by compressing and heating the layer of filter material so that the filter material is fused together. The compressed strip causes an expanded thickness of the side edges to increase the effective filter surface area of the filter and gives the filter a semicircular cross-sectional shape perpendicular to the length of the filter. An adhesive layer is joined to the lower surface of the filter to attach the filter to the fan blade of a ceiling fan.
U.S. Pat. No. 4,676,721 depicts a method and device for reducing the pollution of the air in a room equipped with a ceiling fan having one or more rotating blades comprising covering at least one blade of the fan with porous dust-absorbent material whereby movement of the fan blades removes pollution from the room air.
The above cited inventions are relatively cumbersome to use and maintain, or impractical for use especially in residential locations. None of these inventions effectively deal with the problem of improving air quality while operating the fan and having a means of inexpensively and conveniently renewing the particulate matter adsorption surface.
The present invention is directed to a method and apparatus for removing pollutants from the air and thereby improving air quality. The present invention retains the comfort factors and functionality associated with the use of a fan, such as a ceiling fan, and expands its use for improved adsorption of undesirable pollutants such as particulate matter, without the use of a filter. This invention encompasses the manufacture or modification of a fan and more specifically the blades of a ceiling fan or similar air moving device with an exposed tacky surface preferably over the blade leading edge to which undesirable airborne particulate matter adhere as the blade moves, thus reducing the environmental hazard and improving air quality. It may be appreciated that a moving (or stationary) fan blade does collect some amount of pollutants. Due to its tacky substance, the present invention greatly enhances and expedites the collection process.
Those who have observed fans and more specifically ceiling fans in use can recall the collection of dust and other particulate matter collected on the fan blades, especially the leading edge. Even in what is normally thought to be a clean environment, such as a home residence, there is considerable airborne matter that collects while the fan is operating.
The present invention takes advantage of the rotating fan blade to carry and support an exposed, renewable, tacky adsorption surface to facilitate the collection and retention of the airborne particulate matter without degrading the functionality of the fan itself. As the blade rotates through the air, the particulate matter is adsorbed on the tacky surface. When the surface of the exposed tacky layer is fully or nearly fully covered with pollutants, it is removed and a new clean tacky surface is applied or exposed.
In a preferred embodiment of the invention pollutants are removed from the air. However, it may be appreciated that the principles of the invention may be more generally applied to removing pollutants from any gas.
In accordance with a preferred embodiment of the invention, a method for removing pollutants such as dust, pollen, particulate matter, germs, and the like from a gas such as air, includes:
(a) providing a fan having a fan blade having a surface and a leading edge;
(b) providing a plurality of sheets each sheet having a first side and an opposite second side, a tacky substance being disposed on the first side of each sheet, the plurality of sheets arranged in stacked multi-layer relationship wherein the second side of a sheet rests upon the first side of a next lower sheet;
(c) attaching the second side of a bottom sheet of the stack to the surface of the fan blade around the leading edge of the fan blade so that the first side of a top sheet of the stack is exposed to the gas;
(d) causing the fan blade to rotate through the gas;
(e) observing when the first side of the top sheet becomes contaminated with airborne pollutants;
(f) removing the top sheet of the stack to expose a clean uncontaminated next lower sheet in the stack; and,
(g) periodically repeating steps (e) and (f).
Other aspects of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.